1. Field of the Invention
The present invention relates to an oxyfuel combustion boiler plant and an operation method of the oxyfuel combustion boiler plant.
2. Description of Related Art
A boiler for burning pulverized coal can be divided into two kinds of combustion systems depending on the gas to be supplied to a burner. Air-fuel combustion is of a system for burning fuel by supplying air to the burner. Further, oxyfuel combustion is of a system for burning fuel by a mixture of high purity oxygen and combustion exhaust gas instead of air.
In the oxyfuel combustion, the exhaust gas components are mostly carbon dioxide, so when capturing carbon dioxide from exhaust gas, there is no need to concentrate the carbon dioxide. Therefore, the oxyfuel combustion can pressurize and cool the exhaust gas as it is and liquefy and separate the carbon dioxide, so it is one of the valid methods of reducing the discharge rate of carbon dioxide.
In the oxyfuel combustion system, as a method for accelerating ignition of pulverized coal flowing in the vicinity of the burner, a method for injecting oxygen toward a mixture flow of pulverized coal and combustion exhaust gas is proposed (Patent Document 1).    Patent Document 1: Japanese Patent application Laid-open No. Hei 7 (1995)-318016